Persian Corridor

The Persian Corridor was a supply route through Iran into Soviet Azerbaijan by which British aid and American Lend-Lease supplies were transferred to the Soviet Union during World War II.

This supply route originated in the US and UK with ships sailing around the Cape of Good Hope to the Persian Gulf. From there, the materiel transited Iran to the USSR. Other supply routes included the Northern Route across the north Atlantic, and the Pacific route which handled US cargo at Vladivostok and then used the Trans-Siberian Railway across the USSR.

This Persian Route became the only viable, all-weather route to be developed to supply Soviet needs.

English-language official documents from the Persian Corridor period continue to make the word "Persia" completely interchangeable with name of the nation-state of "Iran." In correspondence by the government of the United Kingdom, usage of "Persia" over "Iran" was chosen by Winston Churchill to avoid possible confusion with neighboring Iraq.

Following Germany's invasion of the USSR in June 1941, Britain and the Soviet Union became allies. Britain and the USSR saw the newly opened Trans-Iranian Railway as an attractive route to transport supplies from the Persian Gulf to the Soviet Union. Britain and the USSR used concessions extracted in previous interventions to pressure Iran (and, in Britain's case, Iraq) into allowing the use of their territory for military and logistical purposes. Increased tensions with Britain led to pro-German rallies in Tehran. In August 1941, because Reza Shah refused to expel all German nationals and come down clearly on the Allied side, Britain and the USSR invaded Iran, arrested the monarch and sent him into exile to South Africa, taking control of Iran's communications and the coveted railway.

In 1942 the United States, by then an ally of Britain and the USSR in World War II, sent a military force to Iran to help maintain and operate sections of the railway. The British and Soviet authorities allowed Reza Shah's system of government to collapse, and they limited the constitutional government interfaces. They put Reza Shah's son, Mohammad Reza Pahlavi onto the Iranian/Persian throne.

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